Improvement in electric circuits for fire and police telegraphs



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ELECTRIC CIRCUIT-FOR FIRE AND POLICE-TELEGRAPH.

No.172,219. Patented Jan.1L,1876.

N FETERS, FHOTO-UTHOGRAPHER, WASHINGTON, D C

UNITED STATES PATENT OFFICE WILLIAM WATKINS, OF JERSEY CITY, NEW JERSEY.

IMPROVEMENT IN ELECTRIC CIRCUITS FOR FIRE AND POLICE TELEGRAPHS.

Specification forming part of Letters Patent No. 172,2 19, dated January 11, 1876 application filed 7 November 23, 1872.

To all whom it may concern:

Be it known that I, WILLIAM B. WATKINS, of Jersey City, State'of New Jersey, have invented certain new and useful Improvements in Electric-Telegraph Circuits for Fire, Police, and Burglar Alarm, and other Telegraphic Purposes; and I do hereby declare that the following is a full description of the same.

I The great objection to the use of the ordinary closed metallic circuit for transmitting signals to a mainor central station for telecommon use for telegraphic purposes.

When such circuits are used for transmitting signals to a central or receiving-station,

for fire, burglar, or police alarm purposes, the delay occasioned in electrically repairing the line when such accidents occur, and the time lost, are often the cause of great loss of life and property.

My improvement in telegraph'circuits not only overcomes the foregoing objections, but

at the same time doubles the capacity of a main metallic circuit when it is clear, so that two separate and distinct sets of signals, or two separate dispatches, may be transmitted or received at the same instant over the one main metallic circuit.

My invention consists, first, in combining with a main metallic circuit the following ele-- ments, viz a permanent earth-connection having an auxiliary battery and receiving-instrument, and at various points on the metallic circuit a series of normally-open earthbranches, with suitable signaling-instruments placed in or connected with the latter and with the metallic circuit, whereby, when any one of the signaling-instruments is operated,

an earth-circuit may be established at intervals, and a signal sent to the receiving-instrument of the permanent earth-connection, and

at the same instant the metallic-circuit iustruments maybe used for communicating intelligence, using the same main wire without interferi'ng with the operation of the earth-circuit instruments, and whereby, when 'a break occurs in the metallic circuit, signals may be sent from all points of the open metallic circuit, on both sides of the break, by means of the earth-connections and signaling-instruments connected therewith, and whereby the same maybe done when the metallic circuit is short-circuited, or when both broken and short-circuited; secondly, in combining, with the elements above set forth, an alarm-instrument with a receiving-instrument of the metallic circuit, which alarm will be operated wheneverthe metallic circuit is broken, so that the line may be kept intact for the purposes set forth; thirdly, in combining magnets and switches with the open earth-branches and metallic circuit, so that the use of the same for telegraphic purposes may be more effectually carried out.

But, to describe my invention more particularly, I will refer to the accompanying drawings, forming a part of this specification, the same letters of reference, whenever they occur, referring to like parts.

Figure 1 is a plan view of the arrangement of the magnets, batteries, circuit of wires, stations, and earth circuits composing the main and auxiliary circuits, to illustrate the use of the said auxiliary circuit in combination With a main circuit of wires.

LetterA is a station for receiving signals, represented within the lines B, having the circuit or line 0 connecting with the pole of the battery D, magnet E, and key F, and thence running to station Gr, itconnects with the binding-screw H, magnet I, key J, binding-screw .K, and, leaving the station, it connects with such instruments as may be required for various telegraphic purposes in the buildings or stations, No.3, No.4, No.5, No.6, No. 7, or any other number desired. The line returns to the pole of the battery D at the station A,

forming a closed metallic. circuit. The magnet E may he used for operating, or bringing into operation, telegraphic instruments of any description, and for any purposes required. The armature L, by suitable connections, maybe made to act as a relay, to operate a local circircuit 0 now being complete, the branch S is attached to any point of the line on either side of the magnet E or battery 1). This branch connects with a closed key, T, with the coils of a magnet, U, battery V, and the earth W.

The magnet U may be used to operate, or bring into operation by the movements of its armature X, such instruments as may be required for all the various telegraphic purposes, such as for sounding and recording the signal numbers of buildings or stations where a fire or burglary has been discovered or is taking place; or both magnets E and U maybe used to operate, or bring into operation, a printingtelegraph of any desired construction when one. magnet is usedto move a type-wheel, so as to bring letters or characters in a position to print impress'ions'of the same upon paper by the movements ot'another armature; or each magnet maybe used to operate a separate dial telegraph-instrument, in a well-known manner. At the station G, and all the .otherstations, there is a switch, 11 which may turn loosely, so as to remain open, as shown; or it may be a springswitch, which will keep closed on the button 0 except when fastened or pressed away. This switch should always remain open when signals or messages are to be received from the main station A; but for all purposes Where the station A is used only to receive messages or signals, such as fire, burglar, or police alarms, the switch I) should be turned as shown by the dotted lines on the button 0 which, connecting with the branch 01?, will then cut out the magnet I and key J. If this is so arranged at each station, the resistance of the line C will be so reduced that a great number of stations may be connected with the circuit, and there will be no keys or magnets in the line outside the main station, except when a message is to be sent 5 then the switch 11 will be opened, as shown, and if the magnet I is not in usewhich will be known if the armature e is not operating-then the desired message or signal may be transmitted to, and answers received from, the station A. The whole force of the battery D will be through the magnets in use only, (E and I in use in this instance,) and will be so powerful that local batteries in any of the buildings or stations outside the main station will not be required. This arrangement of switches is shown and fully described in Letters Patent granted to me January 31, 1871.

At the station G, from any point of the line C or from any of its connections, a branch line, f is run through the coils of the magthe result will be the same.

net g to the spring or key k which, by the:

force ofthe spring, remains open, as shown, The metallic point i connects with the earth).

Now, it will be seen that these branch wires, either with or without the magnet g form a normally open earth branch, and with such branches at the various stations, and with fire-alarm or other signaling boxes suitably connected and set in motion, the circuit may be completed at intervals from' the: main metallic circuit through either of the earth-connections to the earth-battery V, and through the receiving' instrument U, so that the desired signal will be received at the main stationA;

Now, when'the spring or key 702 is alternately closed and opened, either by an operator or by mechanical or electro magnetic mechanism arranged for the purpose, the armature k at station G and armature X at station A- will be operatedv simultaneously, for any desired telegraphic purpose, without affecting the circuit C. The current of the auxiliary eartlrcircuit, when the spring k is closed, will find the path of least resistance. Assuming this to befrom the pole of battery D, in the direction of the arrow, the course of the current will be from the pole of the battery V, through the coils of the magnet U, key T, branch S; thence in the directionof the arrow m to thescrew-post K, through the-coils of magnet 1 earth j and earth W, to the pole of the battery V. If the resistance be equally divided from both sides of the permanent'earth-branch S to the screw-post K;

The current will then take the two paths each side of S, and will unite at K, from which the circuit will be completed, as before. In both cases the armature L of the magnet E and the armature e of the magnet I will not be affected, as the metallic circuit C will not be broken.

At station'No. 7 the connections shown are similar to those at station G. The magnet n and key 0 connect with the line or metallic circuit 0, and the magnet 19 and key g are to be used in connection with the normally open earth-branch r As an illustration of some of the advantages in telegraphy which may be derived from this arrangement of circuits, let operat ors be stationed as follows, viz: Let s and t be at station G with suitable signaling-instruments. Let a and e be at the main receiving-station A, and let to and be at station No. 7 with suitable signaling-instruments.

Now, it will be seen that s and 20 by means of the earth-connections and instruments connected therewith, can comm unieate telegraphically with each other; or signals can be sent by s over the metallic circuit, or over the longest arm thereof, when the metallic circuit is broken at key J by operator t and at the same time t and 11 by the use of the keys J and F of the metallic circuit G and the magnets E and I, can also communicate telegraphically" with each other-that is to say, the camama a i i Pacity. .of, theline C i s donhledpthe use of the auxiliary -earth battery and normall y open earth-branches conneetedtherewithl a.

"It will'be further seen. that operators a and '0? can communicate with each other, while at the same instant to? andu can alsocommunig care with 'each other. Now, if the metallic operator, when he useshis keyhy opening it. The circuit then becomes divided. When broken accidentally,-as at 9 it then becomes divided into two open arms of insulated wires, each connected permanently with tlleiearthbattery'V and receiving-instrument'U, the

wire connectingiwith"and running from the battery V in the direction of the arrow. m

having the series of open earth-branches provided with suitable signaling-instruments at stations 3, 4,, 5,6, and 7, and the other arm or wire having the open earth-branch t j at station Gr. n

a. Now, instantly that a break has. occurred, and a message or signal has to be sent from station No. 7, to the receiving-station A, this can be done notwithstanding the break, for it will be seen that by theuseot' the open earthbranchcsoperator fz'v or s can instantly communicate with a l; or, by the use of suitable signaling instruments, signals may be sent from any of the open-earthbranchesoh either side of thebrenk,;and1willbe receivedon the earth-connected instrumentUbefore the break has been ,repairedLyThe break having been repaired, let i an. accidental ground occur at any point of any of the auniliarybranches, as at 1), station No. -7. This will not interfere with the working otthe instruments in the metallic circuit 0, asit will be seen that by opening the switch]; at any or all of the stations any two of the operators, as at 012,9, and '0 can communicateiwith each other. Now,

remove the ground I), and let a short circuit occur, as at the points c and d. It will be seen that with the ordinary arrangement of the metallic circuit 0, without the improvements of the earth-connections, asdescribed, stations No. 4, No. 5, No. 6, and N0. 7 could not transmit signals to nor communicate with the main station A, but would be cut out entirely until the short circuit was removed;

. but by myarrangement these stations can,

by means of the auxiliary earth-connections, and suitable signaliug-instruments, communicate with the main station A, and at the same time all the other stations can communicate with each other the same as if the short cir- I cuit had not occurred.

iover it for any purpose by the useofi themel openin g it, and must transmit his dispatch by lalterliately opening and 'elosin g it; but when this circuitis thus opened, it th en consists for jthe time being of two open arms, or, in other jgwords, twowires, connected with theone p er-, imanent earth-battery. This, however, ,does not render any part of the line inoperative during the continuance of such break, 1 for will be complete.withoutregardto the break, and whenever anopen earth onthe other side, of the break is closed the same will be true on suchother side ofthefbreak. A break, therefore, howeverlong continued,andl whether by'design or by the accidental severing of,

the wire, does not in anyway interrupter interfere with the perfect operation of the fir e alarmportion of the, line; and thesamewill be true when the line is short-circuited, or when it is at the same moment both short-circuited and broken.

Atthe different stations there is a switch, 0 as shown at station G, which is forced away from the button f by means of the spring 9 When messages are to be received the button f by the operator, so that the branch will be closed, as shown bythe dotted lines, or else the keyh may be pressed on the metallic point i When not in use, the releasing of either the key or spring h, or the switch 63, will leave the auxiliary branch in its. normally opencondition, so ,that any other open earth-branch may be used to transmit signals to thereceiving-station A. If 22 and t are in a communication, and a wishes to call s ,he directs o to notify t to instruct s and the latter immediately closesithe key h or switch c and receives the communication from a on the earth-connections, without interfering with the operations oft and Ben the metallic circuit. The switch 9 is to be used in connection with the earth h when necessary,for dividing the metallic circuit into two separate circuits, so that each may have an independent earth-batteryyalso for locating grounds or other faults, and for throwing oft, when, necessary, a portion of the metallic circuit a i when accidentally broken and grounded.

It will be obvious that the foregoing-de scribed combination of circuitsconstitutes a double-acting circuit, which is capable of being applied for all the variouspurposes of telegraphy by the use of suitable instruments in n combination therewith, among which may be mentioned signaling-instruments for fire, police, burglary, messenger, domestic, and safety railroad signaling purposes, and for public and private telegraphy.

Full descriptions of the same will accompany other applications for patents to complete the series of inventions inconnection with my improved double-acting circuit hereinbefore described.

itallic-circuitinstruments, he must begin by whenever any open earth on one arm. issclosed :the ground-circnit on, that, side of the break from station A, this switch must be held on i strument, connected with the earth or ground W, and with the metallic circuit, and a series of earth-branches, iflj and i, normally open, but having suitable signaling-instruments connected therewith and with the metallic circuit,

for thepurposes set forth.

2. An insulated metallic electric wire, provided with abattery, and having two or more earth-connections normally open, and also a permanent earth, with a battery connected to the wire between said normally open earths, whereby signals" can be sent along the insulated wire in either direction to and from said battery, substantially as described.

' 3. In combination with both arms of a broken metallic circuit, C, and suitable telegraphinstruments for closing and opening the same,

a permanent earth-battery, V, and receivinginstrument operated thereby, and one or more signaling-instruments connected with the insulated wires, but each having an earth-connection normally open, the whole forming a double-acting telegraph, for the purposes set i forth.

- 4. In combination withthe metallic circuit O and earth-circuits, as set forth, one or more I magnets, 9 and 10 in the earth-branches.

5. In combination with the metallic circuit C and earth-circuits, as set forth, the switch g and earth h for the purposes described.

6. In combination with the combined circuits, an alarm apparatus in connection with 1 the armature L of the receiving-instrument'E.

' WILLIAM B. WATKINS.

Witnesses I J. H. MUNSON,

CHARLES L. BARRIIT. 

